1. Field of the Invention
The present invention relates to a retaining plug for assembling or retaining needle roller bearings in the centers of gears. This is achieved by applying a spring force through a push ball and a retaining wire, to separate two of the needle roller bearings and force them against each other and against the inside diameter of the gear.
2. Description of the Prior Art
The prior art retaining plug of FIG. 1 included a cylindrical body having a spring biased and ball detent located in a cavity of the body midway between the ends thereof. The spring biases the ball outwardly against a pair of roller bearings. In use what happens is that the sides of the ball detent would get crushed which would prevent the ball from coming out far enough to retain the needles. Thus, after two or three uses of the prior art plug, they would tip the needle bearings and all of the needle bearings would fall out.
Other devices of the prior art includes Japanese Pat. No. JP02002155963A, entitled, “Device for Preventing Fall-Off of Needle from Needle Bearing in its Assembling”, having a publication date of May 31, 2002. It discloses a device for preventing fall-off of a needle from a needle bearing in its assembling, having a construction by which even if a temporary shaft in an assembling process of the needle bearing is removed, the needle is maintained without falling off, and a permanent shaft can be inserted.
Japanese Pat. No. JP358196939 A., entitled, “Method for Arranging Balls Uniformly and its Device”, was published Nov. 16, 1983. The device arranges balls uniformly by applying an axial load to an inner wheel after inserting balls between the inner and outer wheels. A needle is inserted in sequence in the gap around the balls between the inner and outer wheels thereby arranging the balls uniformly when assembling a ball bearing.
U.S. Pat. No. 2,639,498 (Rookstool) entitled, “Bearing Insert Removing and applying Tool”, issued May 26, 1953, relates to a tool for removing and/or applying the bearing insert for the bearings of a shaft.
U.S. Pat. No. 2,860,406 (Reichardt) entitled, “Roller Bearing Retaining Means”, issued Nov. 18, 1958 illustrates a roller assembly and another roller retention mechanism which is relatively expensive when compared with the present invention. A dummy tubular plug is employed which enters somewhat loosely inside the circular arrangement of the rollers. The plug has two radially bored holes, offset axially, and possibly circumferentially one from the other. There is a formed wire clip which must be entered inside the bore of the tubular plug and the two bent ends fitted radially outward through the bored holes. A resilient rubber-like plug is located inside the bore of the tubular plug to hold the wire clip in place. Thus, this three-piece roller retaining assembly appears to be relatively expensive to manufacture and has to be reused to be feasible. This creates additional expenses for collecting, handling, shipping, storing and cleaning the roller retention mechanism.
U.S. Pat. No. 3,259,962 (Taylor) entitled, “Method of Assembling Bearing Elements, issued Jul. 12, 1966, relates to a method of assembling bearing balls or equivalent roller bearing elements between inner and outer, coaxially and radially spaced bearing members. The method includes the assembly of a circumferential series of bearing members between race surfaces, one of which is machined or fixedly formed upon a part which is journaled by the assembled bearing structure, for example, an elongated worm of a steering mechanism. The worm, in turn, is approximately sustained in a relatively fixed axial relation of its interval race surface to that of the co-acting, radially spaced race surface of a structure in which the end of the worm is axially received.
U.S. Pat. No. 3,345,723 (Stilla et al.) entitled, “Dummy Pin Means and Method for Assembling Needle Bearings”, issued Oct. 10, 1967. It includes a simple form of dummy pin which may be used not only for the assembly of needle or roller bearings having a single roll set, but also for bearing arrangements involving double sets of rolls, with an axially interposed spacer sleeve or collar. The pin further can be arranged to cooperate with the spacer so that it is impossible to assemble a part without inclusion of the spacer.
U.S. Pat. No. 4,166,660 (Murphy) entitled, “Roller Assembly with Roller Retention Spring”, issued Sep. 4, 1979. It discloses a folded spring which extends relatively diametrically across the circle of rollers in a roller assembly with each diametrical side pressing between two adjoining rollers to wedge these rollers apart circumferentially and thus depress all of the rollers against the wall of the bore in a “keystoning” effect with sufficient force to prevent axial movement of the rollers and to radially retain the rollers in the body. The spring may be removed from the body after shipment, preferably by a simple axial push.
U.S. Pat. No. 4,596,472 (Vezirian) entitled, “Thrust Bearing and Axial Retainer System for Rotary Cone Rock Bits and Method for Assembling Same”, issued Jun. 24, 1986. It discloses a retention and thrust bearing system for retaining and locating a rotary rock cutter cone upon a journal shaft supported by a rock bit body. The cone is rotatively supported on the cooperating journal shaft by plain friction roller bearings.
U.S. Pat. No. 6,568,859 (Stegmeier) entitled, “Bearing Support”, issued May 27, 2003. It relates to a rotating shaft bearing mounting structure and, in particular, to a bearing support for facilitating removal and replacement of a bearing and for supporting the rotatable shaft while the bearing is removed from the shaft.
The retaining plug, according to the present invention, substantially departs from the conventional concepts and designs of the prior art, and in so doing, provides a tool primarily developed for the purpose of facilitating insertion of and for retaining the needle roller bearings in the centers of gears by the application of a spring force through the push ball of a detent and the accompanying retaining wire. This separates two of the needle rollers and force them against each other and against the inside diameter of the gear.